Pros: First seat with stay in car base, side impact protection, no rethread harness. Converts to booster.

Cons: $300? Big, hefty seat may not fit in smaller vehicles.

Comments: And now for something totally different: Graco’s Smart Seat is one of the first convertible seats with a stay in the car base (like infant car seats). Yes, you install this base once and then snap in the seat, either front or rear facing. Add in a no rethread harness, six position headrest, seat recline, integrated cup holder and the ability to work as a booster (the base and five-point harness are removed) to 100 lbs. and you have one impressive seat. We also liked how the Smart Seat features side impact protection.

Reader feedback on the seat has been mostly positive, with fans citing its sturdy construction and overall ease of use (one parent joked in an Amazon review the hefty seat was “apocalypse worthy—our son could survive a nuclear attack in this thing”). And that brings up one disadvantage to the Smart Seat: it is a beast, so heavy it can’t be easily moved from vehicle to vehicle. And the large seat size will make rear-facing installations difficult in small or even mid-size cars.

As for crash protection, Consumer Reports testing of the Smart Seat put it in the “good” category—other all-in-one seats like the Evenflo Symphony 65 scored better in crash protection and ease of use. And of course, the Symphony costs a $70-$100 less than the Smart Seat. And the IIHS’s evaluation of the Smart Seat in booster mode was a “Check Fit”—which means the seat may not fit all kids well in booster mode. Other seats were judged better (good or best bet). On the other hand, the Smart Seat earned a perfect five-star rating for ease of use from the NHTSA. So you can see the opinions on this seat are somewhat all over the board.

Bottom line: the Graco Smart is a good bet IF you have a big enough vehicle to install it in. And like all All-in-One seats, this seat sometimes promises more than it delivers.

FYI: Graco has launched two new all-in-one seats since the Smart Seat: the 4Ever and Milestone. We gave those seats higher ratings than the Smart Seat.